mmc: sdhci-of-at91: wait for calibration done before proceed

Datasheet specifies that at the end of calibration the SDMMC_CALCR_EN
bit will be cleared. No commands should be send before calibration is
done.

Fixes: dbdea70f ("mmc: sdhci-of-at91: fix CALCR register being rewritten")
Fixes: 727d836a ("mmc: sdhci-of-at91: add DT property to enable calibration on full reset")
Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20210924082851.2132068-2-claudiu.beznea@microchip.com


Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>